Positioning mechanism



. ly 1965 J. E. LASCHENSKI 3,194,086

POSQETIONING MECHANISM Filed July 13, 1961 4z q% m V /5 F151. F 33United States Patent 3,194,6d6 IGSHTIGNING MECHANlSM Joseph E.Lasehenski, Philadelphia, Pa, assignor, by

mesne assignments, to Philco Corporation, Philadelphia, 79s., acorporation of Delaware Filed July 13, 1961, Ser. No. 123,766 3 tllaims.(El. 74-668) This invention relates to positioning mechanisms, and moreparticularly to mechanisms for positioning rotatable shafts. 1

While of broader applicability, the invention has particular utility inshaft positioning apparatus of the type disclosed and claimed in thecopending application of Albert LaBov, Serial No.728,471, filed April14, 1958, now US. Patent No. 3,065,398, issued November 20, 1962, andassigned to the assignee of the present invention.

The present invention has as its primary obiective the provision ofimproved adjustable indexing means for use inapparatus of theaforementioned type and adapted to operate an electronic tuning devicethrough predetermined sequential angular increments.

Another object of the invention is the provision of adjustable indexingmeans which is characterized by its simplicity of construction andeffectiveness of operation.

A specific object of the invention is the provision of an indexing wheelwhich includes indexing elements that are readily accessible andselectively adjustable by the user.

in a preferred embodiment of the invention there is provided a motorizedself cycling drive mechanism for positioning a rotatable shaft to bemoved sequentially through predetermined angular increments by a motor,each angular increment corresponding to a different television channelas provided by rotatable channel selector means coupled with therotatable shaft. Indexing means is driven with the shaft and is soconstructed and arranged as operatively to engage a switch controllinglever adapted to deenergize the motor when the shaft is rotated to thenext preselected index position. In particular accordance with theinvention, the indexing means comprises a novel programming knob orwheel including a body portion provided with a plurality of axiallyextending keyways within which key elements are slidable, and flexibleand resilient band means encircling said body portion and frictionallyengaging the slidable key elements to maintain positions of the latter.The key elements are disposed parallel to and radially spaced from theaxis of the mounting shaft to provide detent means for controlling theswitch at the selected stations. 'Each key element includes detent meanswithin which the band encircling the knob body is received to maintainpositioning of a key element in its preselected position.

It is a feature of the invention that the shaft to be positioned extendsthrough suitable mounting structure, such for example as a cabinet, oneend of the shaft being adapted to support amanual actuating knob and theother end adapted to support the indexing means. By this novelarrangement, both the knob and the indexing means are visible andaccessible to a user.

From what follows it will be appreciated that the invention alsofeatures controlling mechanism for a switch characterized by its ease ofadjustment, simplicity of construction, and effectiveness of operation.

The manner in which the foregoing objects and advantages may best beachieved will be understoodfrom a consideration of the followingdescription taken in light of the accompanying drawing in which:

FIGURE 1 is a side elevational showin of apparatus embodying theinvention, with parts broken away, and includes an electrical wiringdiagram;

dfi lfi fi Patented July 13, 1965 FIGURE 2 is a front view, inelevation, of the apparatus seen in FIGURE 1, with parts removed; and

FIGURES 3 and 4 are showings similar to FIGURE 1, with parts removed andbroken away, and illustrating novel features of the indexing knob.

Now making more particular reference to the drawing, and first to FIGURE1, a shaft positioning mechanism it) is coupled with a rotatable shaft11 to be driven through predetermined angular increments, said shaftincluding an extension 11a adapted to drive, for example, a televisionchannel selector or tuner 12. Shaft 11 also includes an extension 11bprotruding with clearance through a wall 47 of cabinet structure 45. Aknob 13 is ZIlIlXtDd to extension 11b, whereby manual rotation of shaft11 and tuner 12 is afforded. The positioning mechanism further comprisesreduction gear means (not shown) which may be of known type disposedwithin a housing 14 and affording a drive coupling between the shaft 11'ing 14 and to bracket means 18 affixed to the motor.

Rotor 21 and shaft 22 are axially movable as a unit, in response toenergization and deenergization of the motor. Compression spring 17projects between rotor 21 and housing 14- resiliently to urge the rotorto the extended or deenergized position as shown, Whereas the rotor andits shaft 22 is urged to the left, as seen in FIGURE 3, uponenergization of the motor. The end of shaft 22 journalled within housing14 includes a pinion (not shown) releasably engageable with theaforementioned drive gear means, and in response to the aforementionedaxial movements of rotor 21.

With reference also to FIGURES L2, 3, and 4, novel indexing means 23 forshaft 11 and tuner 12 comprises a knob 24 having a cup-shaped portion 25and acylindrical or barrel-like portion 26 extending therefrom andprovided with keyways 27 within which the indexing keys or key elements31 are slidable. As will be hereinafter more fully explained,preselected keys 31 are moved outwardly of their keyways 2'7predetermined distances to the position shown in FIGURE 1, to providethe desired predetermined angular increments corresponding to televisionchannels of the illustrated tuner 12. p p

In order better to illustrate the cooperative action of the indexingmeans 23 with switch means 33, a key 31 has been removed from theuppermost k'eyway 27 in FIGURE 2. However, it will be understood that akey 31 will be retained within a keyway at all times, either.

in the fully extended positions shown in FIGURE 1 or in the fullyinserted position shown in FIGURE 3.

With more specific reference to the indexing knob 24, and as alreadybriefly described, each of the keys 31 comprises a substantiallyL-shaped elemnet having a generally rectangular main body portion 38.The main body portion 38 comprises the bearing surface of a key 31, andp a the angular or stepped portion 39 comprises stop means which, incooperation with stop means provided in keyway 27, prevents inadvertentremoval of a key 31 from its keyway. Each key 31 is provided with spacedgrooves id, itle which extend transverse its body portion 38 and arealigned along the peripheral surface of the generally cylindricalbarrel-like portion 26 of the knob. A coil spring 43 is tensioned aboutportion 26 and nests within the aligned grooves dtlb of the latter andgrooves dtl, of keys 31, such alignment depending upon the positions ofthe keys. It is this frictional engagement by the resilient spring 43that holds the keys in their selected positions. By this arrangement,keys 31 are slidable within keyways 27 between. the positions providedby the grooves l-(l, ltla, in cooperation with spring 43.

The tab-like ends 44 of keys 31 are disposed within the cup-like portion25 of knob 24 and are accessible through a countersunk opening 4-5provided, for example, in a wall 48 of cabinet structure 45 within whichthe positioning mechanism is disposed. Key ends 44 are formed as tabs toenable an operator to grasp a key 31 and slide the same either to a fullinner or left-hand position (FIGURE 3) or to a full outer or right-handposition (FIGURE 1). It will therefore be appreciated that the inventionis characterized by its compactness and facility of operation, inasmuchas shaft 11 is double ended, having knob 13 at one end, adjustableindexing means at the other end, and mechanism rotatable therewithdisposed intermediate the shaft ends and Within cabinet structure When akey 31 is in its outer position (see also FIG- URE 2), its keyway 27 isvacated for a major portion of its length. An open keyway 2? permits theswitch controlling cam 41 to fall into the open keyway or groove 27,under the urging of resilient switch arm 35, and open switch 33. In theinner position of a key 31 (FIGURE 3), cam 41 will ride along thesubstantially smooth surface presented by knob portion 26 and keys 31,thereby maintaining closure of switch 33, and energization of motor 15,until the cam 41 enters the next successive keyway 27, which operationwill hereinafter be more fully described.

The knob 24 conveniently may be made of molded plastic, as well as maykeys 31. Each of keys 31 is removable from the knob by moving the key toits outer position (FIGURE 1), followed by forcing the tab portion 44-toward the center of the knob (FIGURE 4), against the resilience ofspring 43, to move stop 39 clear of stop 50. At the same time the key ispulled from the keyway 27, thereby removing the same in the generaldirection of the arrow. Conversely, a key is insertable into a keyway byinserting the end provided with a taper 3&1 (FIGURE 4) and forciblyWedging the taper against the spring 43. Continued forcing of the keydisposes either of grooves dila or 4-0 for engagement by the spring,depending upon the desired operational position of the key.

It is a feature of the indexing means that all desired channels orindexed positions are accessible at the same time and can be programmedwithout rotating the tuner to a specific channel position for acceptanceor rejection. Also the knob 24 serves as a rotatable member for manualchannel selection, in which event the knob is grasped by its cup-likeportion 25 that extends through countersunk cabinet opening 46.

With additional reference to the positioning mechansim, motor shaft 22is provided with an electrically non-conductive, cone-like cam member 32which is releasably engageable with the upper, resilient arm 34 ofswitch 33, in response to axial movement of the shaft 2 2. The other, orlower, arm 35 of switch 33 is also resilient, and each of arms 34 and 35are provided with electrical contacts as and 37. Engagement of switcharm 34 by cam member 32 (FIGURES 1, 2 and 4) moves the arm to maintainthe switch contacts 36 and 37 apart to ensure deenergization of motor15. Conversely, disengagement of switch arm 34 by the cam member 32permits resilient arm 34 to move contact 36 toward the closed switchposition for engagement by contact 37 as the latter moves upwardly tomaintain energization of motor 15. Cam portion 41 affixed to switch arm35 is releasably engagcable with indexing keyways 27 formed in indexingknob 24 to control switch arm 35 either to deenergize or maintainenergization of motor 15.

In operation of the apparatus, and with reference to the electricalcircuitry shown in FIGURE 1, initiation of the positioning function isachieved by closing of a momentary switch 42 connected in serieselectrical circuit with line L and motor 15, which closing of the switchenergizes the motor. Immediately upon energization of the motor, rotor21 and shaft 22, along with the cam element 32-, move to the leftmostposition as seen in FIGURE 3. This Cir movement of cam element 32releases resilient switch arm 34. Substantially simultaneously with therelease of switch arm 34, the motor rotationally drives the shaft 11 andthe indexing wheel 24, moving the keyway 27 from the path of the switcharm cam portion 41. The cam portion 41 then is engaged by thecylindrical knob portion 26 and the fully inserted keys 31, in whichinstances arm 35 is so positioned as respects arm 34 to effect closureof the holding switch contacts 36 and 37, which contacts are connectedin parallel electrical circuitry with momentary switch The mechanismwill then move tuner 12 to its next indexed position, which is the nextopen keyway seen in FIGURE 1, whereupon cam portion 41 will engage theopen keyway to open switch 33. This deenergizes the motor and permitsthe rotor to move cam element 32 to its switch engaging position.

Manual rotation of shaft 11 by either of knobs 13 and 2.4 is achievedindependently of the motor drive means while the latter is deenergized,inasmuch as switch 33 is held open through the positive restraint ofresilient actuating arm 34 by cam element 32 mounted on the motor shaft.The positioning mechanism may be caused to operate past undesiredindexed shaft positions by holding the momentary switch 42 closed untilthe shaft has rotated past these positions. Release of the switch justprior to the desired shaft position will of course result in automaticselection of this position by the mechanism.

While no detent means has been illustrated for holding shaft 11 in itsrespective indexing positions it is to be understood that such means maybe provided as an integral part of the driven tuner 12.

I claim:

1. Controlling mechanism for av switch, comprising: rotatable wheelmeans including a cylindrical portion having a plurality of generallyparallel keyways in peripheral surface portions thereof and extendingparallel to the axis of said wheel means, and an axially extendingrecessed portion disposed at one end of said cylindrical portion; andswitch controlling key means disposed within each of said keyways andslidable therein between positions for engaging and disengaging suchswitch means, ends of said key means extending into said recessedportion and comprising tab portions accessible within said recessedportion and providing for adjustable positioning of said key means, eachsaid key means including a step portion and each said keyway including amating step portion, said step portions being disposed and adapted forintereng-agement when a key means is in one of its pair of positionswhereby removal thereof is normally prevented, each said key meansfurther being removable and insertable with respect to a keyway bypivoting of the tab portion thereof toward the axis of said wheel means,whereby to disengage said step portions, then by sliding said key meansrelative to said keyway.

2. Combined indexing Wheel and knob means for positioning a rotatableshaft, comprising: a main barrel portion having axially extendingkeyways defining predetermined indexed positions of a shaft to bepositioned; a generally cup shaped portion aligned axially with saidmain barrel portion, having its opening presented away from the latterand having openings therein aligned with said keyways; an indexing keyelement disposed within each said keyway and slidable therein throughits opening into said generally cup shaped portion between a position inwhich a portion of the keyway is opened at least partially and aposition substantially closing said keyway; and a resilient bandreacting against said barrel portion and frictionally engaging said keyelements to maintain preselected positions of the latter within saidkeyways, said cup shaped portion being configured and disposed toprovide for manual rotation of said shaft.

3. Indexing wheel means according to claim 2, and further characterizedin that each said key element and each said keyway includes abutmentmeans disposed and adapted for interengagement whereby to preventremoval 5 of a key element upon adjustment thereof between its recitedpositions, ends of said key elements being tiltable toward the axis ofthe Wheel means to overcome the recited interengagement to provide forremoval and insertion of the key elements.

References Cited by the Examiner UNITED STATESPATENTS 1,780,328 11/30Ames 74568 Raber 200-38.1 Barrett 74-5 68 X Somes 74568 Neweil 200-3 8Papitto 318-467 Devend-orf 318-467 Jackson 1787.9

Archer 1787.9

1,882,495 10/32 Hipp ZOO-38.1 10 PROUGHTON G. DURHAM, Primary Examiner.

1. CONTROLLING MECHANISM FOR A SWITCH, COMPRISING: ROTATABLE WHEEL MEANSINCLUDING A CYLINDRICAL PORTION HAVING A PLURALITY OF GENERALLY PARALLELKEYWAYS IN PERIPHERAL SURFACE PORTIONS THEREOF AND EXTENDING PARALLEL TOTHE AXIS OF SAID WHEEL MEANS, AND AN AXIALLY EXTENDING RECESSED PORTIONDISPOSED AT ONE END OF SAID CYLINDRICAL PORTION; AND SWITCH CONTROLLINGKEY MEANS DISPOSED WITHIN EACH OF SAID KEYWAYS AND SLIDABLE THEREINBETWEEN POSITIONS FOR ENGAGING AND DISENGAGING SUCH SWITCH MEANS, ENDSOF SAID KEY MEANS EXTENDING INTO SAID RECESSED PORTION AND COMPRISINGTAB PORTIONS ACCESSIBLE WITHIN SAID RECESSED PORTION AND PROVIDING FORADJUSTABLE POSITIONING OF SAID KEY MEANS, EACH SAID KEY MEANS INCLUDINGA STEP PORTION AND EACH SAID KEYWAY INCLUDING A MATING STEP PORTION,SAID STEP PORTIONS BEING DISPOSED AND ADAPTED FOR INTERENGAGEMENT WHEN AKEY MEANS IS IN ONE OF ITS PAIR OF POSITIONS WHEREBY REMOVAL THEREOF ISNORMALLY PREVENTED, EACH SAID KEY MEANS FURTHER BEING REMOVABLE ANDINSERTABLE WITH RESPECT TO A KEYWAY BY PIVOTING OF THE TAB PORTIONTHEREOF TOWARD THE AXIS OF SAID WHEEL MEANS, WHEREBY TO DISENGAGE SAIDSTEP PORTIONS, THEN BY SLIDING KEY MEANS RELATIVE TO SAID KEYWAY.